The present invention relates to panel filters or panel link filters and methods for manufacturing the same.
Heating, ventilation, and air conditioning (HVAC) systems are typically used in conjunction with indoor, commercial, industrial and vehicular systems to regulate temperature and humidity using fresh air from outdoors or system return air. Modern HVAC systems include one or more internal air filters for capturing dust, pollution, and other particulates. The filters remove particulates from the air that could otherwise affect the people indoors or the equipment, products, or processes in the HVAC environment. Filters often determine, at least in part, the heat exchange rate of the HVAC system. The heat exchange rate determines the efficiency of the system and affects the lifetime of equipment. Further, dirty or oversaturated filters can cause overheating during a heating cycle, which could potentially damage the system, or at a minimum, decrease the energy efficiency of the system. Therefore, construction of the filters is pivotal to ensuring that the filter and, in turn, the systems are effective and efficient.
Panel filters or panel link filters are a type of filter that may be used in conventional HVAC systems. Conventional panel filters are constructed by mechanically sealing both the edges of two sheets of media and sealing the sheets at multiple interior locations. The edges of the two sheets of media may be mechanically sealed by RF, ultrasonic, thermal welding or, alternatively, a sewing process, for example. Similarly, the internal seals may be mechanically sealed by RF, ultrasonic, or thermal welding processes. Internal seals exist to reduce “bowing” of the panel filter. If air “bows” the panel filter, the panel filter will distort from its generally planar shape and the filter may release trapped particulates back into the HVAC system. The bowed filter may also rub against the internal HVAC components, leading to panel filter damage. However, the internal sealed regions create substantially air impervious regions in the panel filter, which decrease the area of the panel filter that is capable of capturing air particulates as the sealed area is no longer air permeable. As a result, the effectiveness and efficiency of the HVAC system is reduced.